I have a HP Pavillon Media Center TV M8120N with two 320 GB internal hard drives that came with Vista Home Premium operating system.
I cloned the C drive to an external hard drive and then transferred that clone to the 2nd internal hard drive. The system gave that drive D. My intention was to test using it and then put Windows 7 clean install on Drive C.
I've been booting into the D drive and using it and everything seems fine except I am unable to update any drivers or download anything, presumably because of the drive letter chance, but the downloads don't give me the option of designating a different drive letter.
I have to use Internet Explorer 8 in Vista and it crashes ever time I try to print. I found a .msi file that was suppose to correct the problem, but get a message Windows Installer Service Could Not Be Accessed.
Also I was trying to update drivers from the HP website and was unable to download any of them, presumably for the same reason of the drive letter change. How can I get the system to automatically go to Drive D for downloads and updates?
Thanks.

I have found that whenever trying to play around with multiple startup disks, you're better off disconnecting all the others. Whenever I have built systems I always began with just the startup disk and nothing else connected. Troubleshooting can be a major pain and, if you already know how to clone and disconnect drives, you're better off doing it that way and adding another drive with data on it after boot. Just in my opinion and I think worth doing.